This invention relates to a fuel supplying device for a marine propulsion unit and more particularly to an improved device for insuring that fuel will not be supplied to the engine during ,such times as the engine is being intentionally misfired so as to control its speed and to protect the engine.
It is known to provide ignition systems for internal combustion engines which intentionally misfire the ignition system and spark plugs so as to reduce the speed of the engine when certain conditions are sensed. For example, such misfiring may be done to protect the engine from damage due to over speed, over temperature, lack of cooling water, low oil pressure, low oil supply, or a wide variety of other functions or combinations of them. With most conventional systems, when the spark plug is intentionally misfired, fuel is still supplied to the engine. Not only does this waste fuel, but there is also a danger that backfiring may occur in the exhaust system due to the rich fuel mixture contained therein caused by the misfiring.
It is, therefore, a principal object of this invention to provide an improved engine protection system wherein the engine speed is reduced by misfiring and wherein the fuel supply is also stopped when the engine is being misfired.
It is a further object of this invention to provide an arrangement for avoiding the wastage of fuel at such times when the engine is being misfired.
It is a further object of this invention to provide an interrelated fuel and ignition control that prevents fuel from being supplied to the engine when the engine is being intentionally misfired.